AA GKM24W Internal UV for Aquariums up to 120Ga,Black

Before I purchased the Green Killing Machine I purchased fluval's in-line sterilizer. When using that product I had an outbreak of flukes, which I fought for months. I had to do a major filter tear down on my sixty gallon display tank.But thankfully, that forced me to do more research on uv sterilizers. Apparently most don't cut it, especially for parasite control. Live Aquaria has a great uv sterilizer chart that goes over flow rates and wattages that are most appropriate for your tank. (I included a screenshot of their chart, but the information is also worth a read)This particular model meets my requirements. It's flow doesn't exceed 150gph and it's wattage is high enough to control parasite populations in my tank.The only bummer about the unit at all is that it's large. And it has two ballast boxes. But in a way, that gives me confidence in the unit. Definitely a no bs system. And technically I could have gone with a smaller model (I have a sixty gallon and could probably have used the smaller model) but in the case of uv sterilizers, bigger is better.Installation is straightforward. I don't recommend turning it on and off rapidly -- when you turn it on leave it on for at least a few minutes before turning it off and vise versa (that goes for all advanced lighting systems and will help prevent a blown blub).All in all, I'm grateful that this company is producing an affordable uv sterilizer that's actually robust enough to kill algae and parasites. And I really appreciate not having to touch bulbs ever again.

The media could not be loaded. It’s early, but I never thought I had water clarity issues but wow, this really clears out the water column! I bought to kill any potential bad free floating parasites or algae. But the clarity is amazing after just running over night. I have it in a saltwater Waterbox Infinia Frag 125 gal. I placed it in the sump, in my skimmer tank laying down. Only modification, I put a 1/2” hose from the output pump to run directly to my return pump tank. I don’t want to sterilize and put right back in circulation of same tank, I want to sterilize and pump direct back into my return. Hopefully it holds up, I plan to timer cycle it and not run 24/7 and I plan to maintenance clean the pump for longevity

Maybee im wrong but there is no indicator light to let you know if the bulb is even on or off way to many cords also if u need to replace the bulb its a whole plastic unit jus not a glass bulb seems to work if the bulb is actually working but with no indicator u won't know plus the cords and power blocks and splitters it comes with is absurd

I have a 55 gallon freshwater fish tank that just wouldn't clear up from a bacterial bloom, I let the tank try to cycle itself as I have never liked using chemicals to do what mother nature does on its own. But after 2 weeks of waiting for that to happen, I got impatient and decided to try a UV filter, and due to the severity of the bacterial bloom I went with the 24watt in hopes of it clearing the tank up faster, as you can see from picture (1) to (4), those are taken every day until it cleared. This UV filter I know will work as stated on larger tanks but may take a few more days to complete the process. As I can afford too, I will be adding these to my many tanks as I go along.

Another update - It turned out that the problem was not the bulb so the company replaced the whole thing and its been working well ever since. The company has great customer service and is here in the U.S.IUpdate- I contacted the company and they said the bulb was likely defective and are sending me a new one. So I'm going from 1 star to 3 stars. If it lasts a few months I'll bump it up to 4.I ignored the bad reviews and bought it anyway. Don't waste your money. It worked well but the light stopped working after a few days use. I'd turned it off for a few days to put it on a timer and the light wasn't working when I turned it back on. For some reason I thought it came with a second bulb, so i wasn't in a hurry to replace it. It doesn't and it's too late for me to return it.

This works great . My tank always had a green color in my water. Now it is crystal clear. What an amazing difference. I love the way my tank looks. I love mine so much I bought my daughter one too. I highly recommend this.

Over the years I've purchased several of these units and generally feel that it's a very good product. However, there is one consistent weakness that irritates me more than a little. The external part of the unit has 4 suction cups that in theory but not in fact allow it to be placed on the exterior wall of an aquarium. Alas, I've never had one that didn't lose suction power and simply fall off of my aquarium. There is a simple fix for this flaw. I pull all 4 suction cups off and put a strip of double-sided tape on the unit. I'm clueless about whether this problem is caused by a design flaw or poor quality suction cups.

See the before and after photos. It took about 4 or 5 days to totally clear our 36 gallon aquarium of algae. Now we run it 2 days/week for maintenance.